5/8+4/5= 5/4-1/2= 2/3-1/9=

Bab Bilangan Pecahan
Matematika SD Kelas IV

1] 5/8 + 4/5 = (5 x 5 - 8 x 4)/(8 x 5)
                   = (25 - 32)/40
                   = -7/40

2] 5/4 - 1/2 = (2 x 5 - 1 x 4)/(4 x 2)    
                  = (10 - 4)/8
                  = 6/8
                  = 3/4

3] 2/3 - 1/9 = (2 x 9 - 3 x 1)/(3 x 9)
                  = (18 - 3)/27
                  = 15/27
                  = 5/9

• 5/8 + 4/5
= 25/40 + 32/40
= 57/40
= 1 17/40

• 5/4 - 1/2
= 5/4 - 2/4
= 3/4

• 2/3 - 1/9
= 6/9 - 1/9
= 5/9